news, etc. pluto demoted! (now a “dwarf planet”) pluto demoted! (now a “dwarf planet”) new...
TRANSCRIPT
News, etc.News, etc.
Pluto Pluto demoted! demoted! (Now a “dwarf (Now a “dwarf planet”)planet”)
New rule: New rule: shaped by shaped by gravity and …gravity and …
Dominates its Dominates its neighborhoodneighborhood
News continued…News continued…
Charlotte Talks Charlotte Talks this morning this morning (WFAE 90.7 / 90.3 (WFAE 90.7 / 90.3 ) wfae.org, on ) wfae.org, on “Science and “Science and Religion,” with Dr. Religion,” with Dr. Mike Corwin, Mike Corwin, UNCCUNCC
Posted in mp3 on Posted in mp3 on WebCTWebCT
Lab tonight and SundayLab tonight and Sunday
TONIGHT: “Meet and Greet” sessionTONIGHT: “Meet and Greet” session May receive lab manual binderMay receive lab manual binder SUNDAY: Need lab manual! SUNDAY: Need lab manual!
(Bookstore)—will do lab #1 on (Bookstore)—will do lab #1 on constellations! Read Introduction in constellations! Read Introduction in advance! (Quiz possible.)advance! (Quiz possible.)
Topics Survey ResultTopics Survey Result
10. What makes a planet? 10. What makes a planet? 9. Navigation by stars9. Navigation by stars8. Paranormal8. Paranormal7. Comets, meteors and 7. Comets, meteors and
asteroids, oh my!asteroids, oh my!6. Space travel physics6. Space travel physics5. Extraterrestrial life5. Extraterrestrial life4. Stars!4. Stars!3. Paranormal3. Paranormal2. Black Holes2. Black Holes1. Constellations1. Constellations
Astrology resultsAstrology results
52 filled out and 52 filled out and turned in (with one turned in (with one choice)choice)
3 picked their 3 picked their “correct” sign “correct” sign descriptordescriptor
What would we What would we expect?expect?
Is it Is it significant significant ?? One year: 3 sigmas!?!One year: 3 sigmas!?!
Scale of the Scale of the Universe Universe
How big and far away is How big and far away is stuff?stuff?
Earth-MoonEarth-Moon
Earth ~8k miles Earth ~8k miles in diameterin diameter
Rotates?Rotates? Moon about a ¼ Moon about a ¼
of the Earth sizeof the Earth size Moon is ~100 of Moon is ~100 of
its diameters its diameters awayaway
Solar systemSolar system
Earth-Sun Earth-Sun distance is the distance is the “astronomical “astronomical Unit” (AU) Unit” (AU)
Planets at 0.4, 0.7, Planets at 0.4, 0.7, 1 (us!), 1.5, 5, 10, 1 (us!), 1.5, 5, 10, 20, 40 Aus, and …20, 40 Aus, and …
Sizes not to scale!
Sun
New (now, dwarf) planet – New (now, dwarf) planet – 7/31/057/31/05
96 AUs96 AUs Really a Really a
Kuiper Belt Kuiper Belt object?object?
Orbit Orbit inclined 45 inclined 45 degreesdegrees
““Xena”?Xena”?
Nearest StarNearest Star
4.2 light years (ly) 4.2 light years (ly) awayaway
c = 3 x 10c = 3 x 1055 km/s km/s 1 ly ~ 9.5 x 101 ly ~ 9.5 x 101212
km or about km or about 63,000 AU63,000 AU
So nearest star is So nearest star is 4.2 times this or 4.2 times this or about 265,000 AUsabout 265,000 AUs
Our Milky Way GalaxyOur Milky Way Galaxy
MWG about MWG about 100,000 ly in 100,000 ly in diameterdiameter
We are ~ 2/3 the We are ~ 2/3 the way outway out
Nearest Galaxy, in Nearest Galaxy, in AndromedaAndromeda
2 million light 2 million light years awayyears away
(about 20 (about 20 MWG MWG diameters)diameters)
The “Local Group”The “Local Group”
A few dozen A few dozen galaxiesgalaxies
Spread over a Spread over a few Mlyfew Mly
Nearest Large GroupNearest Large Group
Virgo Virgo Cluster ~60 Cluster ~60 Mly away Mly away (20 LG (20 LG dia’s)dia’s)
~ 1000 ~ 1000 member member galaxies in galaxies in itit
ObservableObservable Universe ~ Universe ~ 14.7 Gly14.7 Gly
Hubble Deep FieldHubble Deep Field